If you've been following along over about the last nine months here in the magazine, you've seen us building up our latest trail Toyota. What started life as a 2001 2WD Prerunner has transformed into a rig capable of crawling rocks or transporting us to our favorite back-country camp spots.
When we decided to build up an early Tacoma, we chose to use the Prerunner as our base as they are often readily available in good condition and cost a few thousand less than a comparable 4WD model. Both models use the same frame and we had plans for replacing all the drive train, save for the 3.4L V-6 motor and the four-speed auto tranny. Both of these have proven to be reliable and to perform well.
We shed the truck of all the axle, suspension, and steering parts and then reinforced the rear frame rails and raised the gas tank about 3 inches for clearance. We decided to keep the bed length stock, but opened all the fender wells to make room for articulating 37-inch rubber. We also trimmed the tail sheet metal so we could build a bumper tucked up high so that we keep the tail from dragging when we cross deep ravines.
Our foundation started with a set of Solid Axle built D60 units to provide plenty of axle strength. The front is 65 inches from flange to flange and the rear full-floater comes in at 64 inches. This yields us an outside track width just shy of 80 inches. This width provides good stability while still being able to fit through tight trails without a lot of fuss. The Solid D60s are stuffed with ARB air lockers, Yukon 5.13 gears, 35-spline alloy shafts, and Warn hubs up front. Both differentials are high-pinion units and use 1350 yokes.
To turn the 2WD into 4WD, we installed an Inchworm-built adapter onto the Prerunner auto tranny and mated that to a 23-spline, 2.28:1 Toyota gear reduction box. Behind that comes an Advance Adapters kit that mates the reduction unit to a 3:1 Atlas II transfer case with 32-spline outputs and 1350 CV yokes. From this we get four transfer case ratios and some deep gearing for slow crawling when we want. This combination works great and we can use the low gearing for effective compression braking on steep ascents.
Front suspension comes from All-Pro Off-Road. We took their Taco Supreme kit and mated it to the D60 with some bracket changes at the axle end. This three-link kit went cleanly on the frame after all the stock IFS was cut and ground away. Twelve-inch-travel Walker Evans coil-overs provide a smooth ride and a comfortable spring rate both on and off the highway. We're using the adjustable reservoir model and like being able to tweak the dampening to suit the terrain we're on.
All-Pro leaf packs prop up the rear and their 5-inch version spring gives us good ride height and we are pleased with how well they flex to compliment the front articulation. We use Bilstein 7100 reservoir shocks for dampening at the tail.

In the belly of the truck...

In the belly of the truck lies the Toy reduction box and 3:1 Atlas II transfer case that give us front and rear drive power. Some substantial cab floor sheet metal work was needed to tuck the massive Atlas up high to get us the ground clearance we wanted. We now have three t-case shift levers poking through our floor.

Under the front of the truck...

Under the front of the truck lies a Solid Axle D60 supported with an All-Pro Off-Road Taco Supreme link suspension kit. The kit uses two lower links, one upper link on the top of the differential, and a panhard bar. The guys at J.E. Reel Drive Line Specialists took our build dimensions and crafted us a pair of beefy 1350-based CV driveshafts to mate the Atlas output yokes to the axle yokes. The high-pinion differentials help keep the driveshafts up out of harms way.

A Toyota IFS truck steering...

A Toyota IFS truck steering box has been mounted to the reinforced front framerail. The box has been ported for hydro assist hoses and a 1.5-inch-diameter PSC assist cylinder helps turn the tires with power from a PSC pump. Budbuilt heavy duty draglink and tie rod are hooked to a custom pitman arm and to the Solid Axle steering arms.